MEMORY POPULATION RULES INSTALLING HARDWARE
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Memory Population Rules
When considering the memory configuration of your server, you should consider the fol-
lowing items:
DIMMs within the server should all be the same size, speed, and type. It is not recom-
mended to mix different sized or different speed DIMMs in the same system. Mixing
DIMM modules results in the system setting the memory speed to that of the slow-
est installed DIMMs.
There are white and black DIMM slots. Populate the white slots in a bank first.
DIMMs can be used either in a one DIMM per Channel (1DPC) configuration or in a
two DIMMs per Channel (2DPC) configuration.
Low-voltage (1.35 V) DIMM and standard-voltage DIMM (1.5 V) can be mixed in the
system. However, the system BIOS defaults to standard-voltage operation.
The following denotes the memory support matrix.
Table 1: Memory Support Matrix
2 SPC
1 DPC 2 DPC
1.5V
SR/DR 1600 1600
QR 1066 800
LRDIMM 1333 1333
1.35V
SR/DR 1600(*) 1333
QR 1066(*) 800
LRDIMM 1333(*) 1333(*)
Table 2: Memory Population Configuration
DIMM_A1 DIMM_A2 DIMM_B1 DIMM_B2 Mirror Spare Lockstep
Configuration 1 x
Configuration 2 x
Configuration 3 x x o
Configuration 4 x x o
Configuration 5 x x o o
Configuration 6 x x x
Configuration 7 x x x
Configuration 8xxxxooo
x: Indicates the DIMM population location.
o: Indicates the supported function.